TOMMUNIKATI NI A HARMONIA NINI - … · TOMMUNIKATI NI A HARMONIA NINI US009818512B2 ( 12 ) United...

TOMMUNIKATI NI A HARMONIA NINI US009818512B2

( 12 ) United States Patent Martin et al .

( 10 ) Patent No . : US 9 , 818 , 512 B2 ( 45 ) Date of Patent : Nov . 14 , 2017

( 56 ) References Cited ( 54 ) THERMALLY SPRAYED THIN FILM RESISTOR AND METHOD OF MAKING U . S . PATENT DOCUMENTS

@ ( 71 ) Applicant : VISHAY DALE ELECTRONICS , LLC , Columbus , NE ( US )

@ ( 72 ) Inventors : Tom J . Martin , Niagara Falls , NY ( US ) ; Clark Smith , Columbus , NE ( US ) ; Jeff Traikoff , Niagara Falls , NY

4 , 152 , 689 A 5 / 1979 Thompson 4 , 677 , 413 A 6 / 1987 Zandman et al . 4 , 808 , 490 A 2 / 1989 Tsukuda et al . 5 , 966 , 067 A 10 / 1999 Murakami et al . 6 , 136 , 512 A 10 / 2000 Doeling 6 , 153 , 256 A 11 / 2000 Kambara et al . 6 , 201 , 290 B1 . 3 / 2001 Yamada et al . 6 , 242 , 999 B1 6 / 2001 Nakayama et al .

( Continued ) ( US )

( 73 ) Assignee : VISHAY DALE ELECTRONICS , LLC , Columbus , NE ( US ) FOREIGN PATENT DOCUMENTS

@ ( * ) Notice : Subject to any disclaimer , the term of this patent is extended or adjusted under 35 U . S . C . 154 ( b ) by 113 days .

1 271 566 A2 1 / 2003 H08 - 203713 A 8 / 1996

( Continued )

( 21 ) Appl . No . : 14 / 563 , 560 OTHER PUBLICATIONS @

( 22 ) Filed : Dec . 8 , 2014 Leyman , “ Supersonic Particle Deposition ( Cold Spray ) , ” US Army Research Laboratory , Weapons & Materials Research Doctorate , HCAT Program Review Meeting , Jul . 20 - 21 , 2004 ( 24 pages ) .

( Continued ) ( 65 ) Prior Publication Data

US 2016 / 0163432 A1 Jun . 9 , 2016 ( 51 )

( 52 )

Int . CI . H01C 17 / 075 ( 2006 . 01 ) HOIC 7700 ( 2006 . 01 ) HOIC 1 / 012 ( 2006 . 01 ) HOIC 1 / 142 ( 2006 . 01 ) HOIC 17 / 28 ( 2006 . 01 ) U . S . CI . CPC . . . . . . . HOIC 177075 ( 2013 . 01 ) ; HOIC 1 / 012

( 2013 . 01 ) ; HOIC 1 / 142 ( 2013 . 01 ) ; HOIC 7 / 006 ( 2013 . 01 ) ; HOIC 17 / 283 ( 2013 . 01 )

Field of Classification Search CPC . . . . . . . H01C 1 / 012 ; H01C 1 / 142 ; HO1C 7 / 006 ;

HO1C 17 / 075 ; HO1C 17 / 283 See application file for complete search history .

Primary Examiner — James Harvey ( 74 ) Attorney , Agent , or Firm — Volpe and Koenig , P . C . ( 57 ) ABSTRACT A thin film resistor formed using thermal spraying tech niques in the manufacturing process is provided . A thin film resistor and method of manufacturing a thin film resistor are disclosed including a thermally sprayed resistive element . An alloy bond layer may be applied to a substrate and a thermally sprayed resistive layer is applied to the alloy bond layer by a thermal spraying process to form a thermally sprayed resistive element . The alloy bond layer and the thermally sprayed resistive layer may have the same chemi cal composition .

30 Claims , 18 Drawing Sheets

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( 56 ) References Cited =

U . S . PATENT DOCUMENTS = = = = = =

2001 143905 A 2002 184602 A 2002 - 305126 A 2002 299203 A 2003 - 124004 A 2003 - 203801 A 2003 - 282302 A 2003 - 282304 A 2003 - 282305 A 2005 - 258302 A 2006 024767 A 2006 - 186064 A 2007 - 095926 A 2011 - 091140 A 2011 - 238730 A

5 / 2001 6 / 2002

10 / 2002 11 / 2002 4 / 2003 7 / 2003

10 / 2003 10 / 2003 10 / 2003 9 / 2005 1 / 2006 7 / 2006 4 / 2007 5 / 2011

11 / 2011

= = = = = = = =

OTHER PUBLICATIONS

6 , 428 , 630 B1 8 / 2002 Mor et al . 6 , 762 , 396 B2 * 7 / 2004 Abbott . . . F27D 11 / 02

118 / 724 6 , 943 , 662 B2 9 / 2005 Tanimura 7 , 057 , 490 B2 6 / 2006 Hashimoto et al . 7 . 098 . 768 B2 8 / 2006 Doi 7 , 782 , 173 B2 8 / 2010 Urano et al . 7 , 839 , 000 B2 11 / 2010 Mis et al . 7 , 982 , 582 B2 7 / 2011 Belman et al . 8 , 514 , 051 B2 8 / 2013 Belman et al . 8 , 957 , 756 B2 2 / 2015 Belman et al .

2002 / 0031860 A1 3 / 2002 Tanimura 2002 / 0148106 Al 10 / 2002 Tsukada et al . 2003 / 0117258 AL 6 / 2003 Kim et al . 2004 / 0262712 AL 12 / 2004 Doi 2008 / 0094169 Al 4 / 2008 Kinoshita et al . 2009 / 0308454 AL 12 / 2009 Korevaar et al . 2011 / 0100975 A1 5 / 2011 Liu et al . 2011 / 0188838 A1 * 8 / 2011 Abbott . . . F27D 11 / 12

392 / 407 2012 / 0126934 AL 5 / 2012 Belman et al . 2014 / 0308883 Al * 10 / 2014 Sung . B24B 53 / 017

451 / 443 2016 / 0035466 Al * 2 / 2016 Xu . . . . . . . . . . . . . . . . . . . . . . . . . . · HOIC 1 / 14

338 / 20 2016 / 0145159 A1 * 5 / 2016 Landwehr . . . . . . . . . . . . . C04B 41 / 52

428 / 448 2016 / 0163432 A1 * 6 / 2016 Martin . . . . . . . . . . . . . . . . . H01C 17 / 075

338 / 308

Sulzer Metco , “ An Introduction to Thermal Spray , ” Issue 4 , copy right 2012 ( 24 pages ) . The year of publication is sufficiently earlier than the effective U . S . filing date and any foreign priority date so that the particular month of publication is not in issue . Inovati , “ KM - Production Coating System , ” KM Data Sheet , Form PCS - 10 , copyright 2010 ( 1 page ) , downloaded from http : / / www . inovati . com / . The year of publication is sufficiently earlier than the effective U . S . filing date and any foreign priority date so that the particular month of publication is not in issue . Gabel , Howard , “ Kinetic Metallization Compared with HVO , " Advanced Materials and Processes / May 2004 ( pp . 17 and 48 ) . Vishay Intertechnology , Inc . , “ Resistors 101 , " Instructional Guide , date code “ VMN - SG2113 - 1205 " referring to publication in 2012 , pp . 1 - 8 . The year of publication is sufficiently earlier than the effective U . S . filing date and any foreign priority date so that the particular month of publication is not in issue . FOREIGN PATENT DOCUMENTS

2001 023801 A 2001 110601 A

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THERMALLY SPRAYED THIN FILM about at least 10 micrometers per minute . The high depo RESISTOR AND METHOD OF MAKING sition rate of thermal spraying allows low value resistors to

be made at a more competitive cost than known techniques . FIELD OF THE INVENTION In contrast to thermal spraying , a PVD process cannot

5 achieve the thicknesses required in a practical time period . The present invention relates to the field of resistors , and Thermal spraying , while typically performed in ambient

more particularly , to a thin film resistor made at least in part conditions , can also be performed under a range of envi having thermally sprayed layers and using thermal spraying ronments or conditions to control the oxide level and , to techniques . some extent , the structure of the thermally sprayed material .

10 An advantage to spraying in ambient conditions is a reduc BACKGROUND tion in processing time due to lack of required pump down

time of a vacuum or other environmentally controlled sys Thin film resistors are typically manufactured by depos - tem . Thermal spraying technologies available in the industry

iting resistive films of various alloys onto a non - conductive vary by the method of applying material , for example , the substrate . Typically , an aluminum oxide or aluminum nitride 15 type of energy used and by the type of material used as the ceramic substrate is used , but other substrate materials can feedstock . be used including , but not limited to , glass , diamond , ruby The present invention provides a means to address the and metallic substrates having a non - conductive coating time constraint and cost problems associated with deposition The deposited films range in thickness from a few hundred of resistive elements in thin film resistors using known Angstroms to several thousand Angstroms , depending on the 20 techniques , by the application of thermal spraying technolo desired sheet resistance . gies to the manufacture of thin film resistors .

Formation of the resistive films can be accomplished through a range of processes including plasma enhanced SUMMARY OF THE INVENTION chemical vapor deposition ( PECVD ) , chemical vapor depo sition ( CVD ) or physical vapor deposition ( PVD ) , with PVD 25 In order to minimize the process time and cost in manu being the most typical method used for thin film resistor facturing thin film resistors , thermal spraying processes and manufacturing . Film deposition with a PVD process is technologies , typically used in a range of industries for rapid typically performed in a vacuum environment . Deposition deposition of materials for mechanical wear purposes , cor rates for a PVD process vary between about 0 . 005 to about rosion resistance , restoration of surfaces and thermal barri 0 . 2 micrometers per minute for typical materials used in 30 ers , may be used to deposit a resistive element on a substrate , resistor manufacturing . and also to deposit other materials and layers , to form a thin

In thin film resistor design , the resistor value may be film resistor , according to the teachings of the present determined through the combination of the sheet resistance invention . of the deposited film , measured in Ohms / Square , and the It is therefore an object , feature , or advantage of the number of squares defined by the resistor geometry . For 35 present invention to provide a thin film resistor that uses example , a 100 ohm resistor can be manufactured using a 50 thermal spraying techniques in the manufacturing process . ohm / square film and a design that has a two ( 2 ) square According to an aspect of the present invention , a thin resistor geometry . film resistor is provided comprising a thermally sprayed

While PVD thin film technologies are effective at manu - resistive element . The resistive element may be formed as a facturing precision resistors at nominal values of 10 ohms or 40 thermally sprayed layer comprising a material that has been above , the feasibility of creating lower resistance values , thermally sprayed on at least a portion of the surface of a such as those in the range of about 10 ohms or less , or about substrate or on a selected layer of the thin film resistor . 1 ohm or less , diminishes rapidly due to limitations in According to another aspect of the present invention , a achieving the necessary film thicknesses in a practical and thin film resistor is provided with an alloy bond layer commercially reasonable time period . Accordingly , there is 45 deposited on at least a portion of the surface of a substrate . a need for a process for manufacturing a resistor that is faster thermally sprayed resistive layer is thermally sprayed on than known techniques , yet is still precise , efficient and cost at least a portion of the alloy bond layer to form a thermally effective . sprayed resistive element .

Thermal spraying is a process whereby heat is used to A method of making a thin film resistor is also provided . soften a material such as a metal or a ceramic , and then 50 In an embodiment , a thin film resistor is formed by thermally particles of the softened material are propelled , such as by spraying a selected material on a surface of a substrate , or on a gas , onto a substrate to be coated . Other forms of energy , a selected layer of the thin film resistor , using a thermal such as kinetic energy , may be used to accelerate the spraying process to form a thermally sprayed resistive particles to a velocity whereby plastic deformation occurs element . when the particles impact the substrate . The particles form 55 In another aspect of the present invention , a method of a dense coating / layer on the substrate as the particles manufacturing a thin film resistor is provided , wherein an agglomerate . The material to be thermally sprayed is some - alloy bond layer is applied to at least a portion of a surface times referred to as the “ feedstock . ” An example of equip of a substrate , and a thermally sprayed resistive layer is ment used for thermal spraying , and equipment that may be applied , by a thermal spraying process , to at least a portion used for making a thin film resistor according to the present 60 of the alloy bond layer , to form a thermally sprayed resistive invention , is the Kinetic Metallization : Production Coating element . System , KM - PCS , offered by the Inovati Company of Santa In another aspect of the present invention , a thin film Barbara , Calif . resistor is provided comprising a substrate having a first

Thermal spraying techniques can deposit metals at rates surface and an opposite second surface , an alloy bond layer several times faster than PVD , PECVD or CVD processes 65 deposited on at least a portion of the first surface of the generally used to form thin film resistors . For example , substrate , and a thermally sprayed resistive layer thermally thermal spraying can deposit materials at a deposition rate of sprayed on at least a portion of the alloy bond layer .

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US 9 , 818 , 512 B2

Conductor pads are provided adjacent sides of the thermally BRIEF DESCRIPTION OF THE DRAWINGS sprayed resistive layer and extending along a portion of the alloy bond layer . The conductor pads may comprise first A more detailed understanding may be had from the conductor layers and second conductor layers . Adhesion following description , given by way of example in conjunc layers may be applied beneath the first conductor layers . An 5 tion with the accompanying drawings wherein : electrical connection is provided from a first surface of the FIG . 1 shows a cross - sectional view of a film resistor resistor to a second opposite surface of the resistor . Alloy according to an embodiment of the present invention . adhesion layers are applied extending from adjacent the FIG . 2 shows an enlarged cross - sectional view of a conductor pads , along the sides of the substrate , and along portion of the film resistor according to an embodiment of portions of the second surface of the substrate . Third con - 10 the present invention shown in FIG . 1 . ductor layers may be applied over the adhesion layers . FIG . 3 shows an enlarged cross - sectional view of a Additional fourth conductor layers may be applied over the portion of a resistor according to an embodiment of the third conductor layers . Barrier layers may be applied over invention designated as “ FIG . 3 ” in FIG . 2 . the fourth conductor layers . A solder finish may be provided 10 FIG . 4 shows an enlarged cross - sectional view of a over the barrier layers . portion of a resistor according to an embodiment of the

In yet another aspect of the present invention , a method of invention showing the area designated as " FIG . 4 ” in FIG . forming a thin film resistor is provided , comprising the steps 2 . of : providing a substrate having a first surface , side surfaces , FIG . 5 shows an enlarged cross - sectional view of a and a second surface opposite the first surface ; depositing an 20 portion of a resistor according to an embodiment of the alloy bond layer over at least a portion of the first surface ; invention showing the area designated as “ FIG . 5 ” in FIG . thermally spraying a thermally sprayed resistive layer over 2 . at least a portion of the alloy bond layer ; forming conductor FIG . 6 shows an enlarged cross - sectional view of a pads adjacent sides of the thermally sprayed resistive layer ; portion of a resistor according to an embodiment of the providing an overcoat over exposed parts of the thermally 25 invention showing the area designated as “ FIG . 6 " in FIG . sprayed resistive layer ; and , electrically connecting the first 2 surface and the second surface of the resistor . FIG . 7 shows a top plan view of an exemplary mechanical Forming conductor pads may comprise the steps oT : mask for use in applying an alloy bond layer and thermally depositing adhesion layers adjacent sides of the thermally sprayed layer to a resistor according to the present invention . sprayed resistive layer and over portions of the alloy bond 30 FIG . 7A shows a cross - sectional view of the width of an layer ; depositing first conductor layers over the adhesion opening in the mechanical mask shown in FIG . 7 , taken layers ; and plating second conductor layers over the first

conductor layers . along line A - A in FIG . 7 . FIG . 7B shows a cross - sectional view of the length of an Providing an overcoat may comprise the steps of : pro

viding a moisture passivation layer over at least a portion of 35 ope 35 opening in the mechanical mask shown in FIG . 7 , taken the thermally sprayed resistive layer ; and providing a aved resistive laver and providing a along along line B - B in FIG . 7 . mechanical protection laver over at least a portion of the FIG . 8A shows a top surface of a resistor made according moisture passivation layer . to the teachings of the present invention .

Electrically connecting the first surface and the second FIG . 8B shows a bottom surface of a resistor made surface may comprise the steps of : depositing adhesion 40 according to the terms of the present invention . layers adjacent the conductor pads , along portions of the first FIG . 9 is a flow diagram illustrating a part of a manufac surface and sides of the substrate , and at least partially along turing process of an embodiment of a thin film resistor of the portions of the second surface of the substrate ; depositing present invention . third conductor layers over the adhesion layers ; and , plating FIG . 10 is a flow diagram illustrating a part of a manu fourth conductor layers over the third conductor layers . 45 facturing process of an embodiment of a thin film resistor of Barrier layers may be applied over the fourth conductor the present invention . layers , and solder may be applied over the barrier layers . FIG . 11 is a flow diagram illustrating a part of a manu

The alloy bond layer and the thermally sprayed resistive facturing process of an embodiment of a thin film resistor of layer may have a similar chemical composition . The ther - the present invention . mally sprayed resistive layer may be chemically bonded to 50 FIG . 12 is a flow diagram illustrating a part of a manu an alloy bond layer selected to have a similar chemical facturing process of an embodiment of a thin film resistor of composition . In another embodiment of the present inven the present invention . tion , the alloy bond layer and the thermally sprayed resistive FIG . 13 is a cross - sectional view of a portion of an layer may have dissimilar chemical compositions . embodiment of a resistor according to the present invention ,

In another aspect of the present invention , the thermally 55 showing a thermally sprayed resistive layer thermally sprayed resistive layer is deposited by a thermal spraying sprayed directly to a substrate . process at a rate of about between about 10 to 60 microm - FIG . 14 is a cross - sectional view of a portion of an eters per minute . In another aspect of the present invention , embodiment of a resistor according to the present invention , the thermally sprayed resistive layer is deposited by a showing the alloy bond layer extending along a portion of thermal spraying process at a rate of about at least 10 60 the upper surface of the substrate . micrometers per minute . FIG . 15 is a cross - sectional view of a portion of an

In another aspect of the present invention , the thermally embodiment of a resistor according to the present invention , sprayed resistive element comprises an alloy of copper , showing a thick film conductor . nickel , tantalum or titanium . FIG . 16 is an image of a cross - section of a portion of an

In another aspect of the present invention , the alloy bond 65 exemplary resistor made according to the teachings of the layer comprises an alloy of copper , nickel , tantalum or present invention , using bright field illumination at 5x titanium . magnification .

US 9 , 818 , 512 B2

FIG . 17 is an image of a cross - section of a portion of the may be referred to herein as the " thermally sprayed material exemplary resistor of FIG . 16 , using bright field illumination 16 . ” The thermally sprayed material 16 will be used as the at 10x magnification . feedstock for a thermal spraying process , to apply , by

FIG . 18 is an image of a cross - section of a portion of the thermal spraying , the thermally sprayed resistive element 20 exemplary resistor of FIG . 16 , using bright field illumination 5 of a finished resistor . at 25x magnification . A potential difficulty with applying a thermally sprayed

FIG . 19 is an image of a cross - section of a portion of the material to a ceramic or other non - metallic substrate lies in exemplary resistor of FIG . 16 , using bright field illumination achieving a substantial bond strength , e . g . , a bond that will

not readily separate , between the thermally sprayed material at 25x magnification . FIG . 20 is a cross - sectional view of a portion of an on 10 and the underlying substrate or surface . For example , during

embodiment of a resistor according to the present invention , the thermal spraying process on ceramic or non - metallic materials , a bond is achieved which is primarily mechanical . showing a thermally sprayed conductor layer . In typical thermal spraying applications , the surface of the

DETAILED DESCRIPTION OF THE substrate is grit blasted to remove oxides and to texture the surface thereby promoting mechanical adhesion between the INVENTION feedstock and the substrate . However , in the manufacture of thin film resistors , the The present invention is directed to the use and applica thickness of the ceramic substrate ranges generally between tion of thermal spraying processes , techniques and technolo about 0 . 010 inches to 0 . 025 inches thick . Grit blasting of gies to the manufacture of thin film resistors . Table 1 , 20 ceramic or non - metallic substrates of such a thickness can provides a summary of typical thermal spraying processes , result in distortion of the substrate well before a sufficient energy sources , environmental conditions , and the types of surface roughness is achieved . Thus , known grit blasting feedstock that may be used . Any of these methods could be techniques are inappropriate , and generally inapplicable , to used to achieve the rapid material deposition rates required the process of making a thin film resistor . for low resistance value thin film resistor manufacturing , as , 25 In order to create a strong bond between the ceramic or well as any others understood in the art to fall within the non - metallic surface of the substrate 12 and the thermally scope of thermal spraying . sprayed material 16 that will form the thermally sprayed

resistive element 20 of the resistor according to the present TABLE 1 invention , an alloy bond layer 14 is deposited on the

Type of 30 substrate 12 . The alloy bond layer 14 may comprise , for Thermal Type of Energy Spray Process Type of example , a nickel chromium alloy . Other alloys may be used Spray Process Source Environment Feedstock depending on the alloy used for the thermally spray material

that will be applied . The alloy bond layer 14 , may comprise , Atmospheric High Temperature Ambient Powder Plasma Spray Plasma but is not limited to , alloys comprising nickel , tantalum , High Velocity High Ambient Powder 35 titanium , copper and aluminum , other known alloys suitable Oxygen Temperature for use as the alloy bond layer , or combinations thereof . The Fuel ( HVOF ) Combustion alloy bond layer 14 is preferably applied by a PVD process , Electric Wire Arc Thermal Energy Ambient Wire

From Wire Arc but it is appreciated that other thin film deposition technolo Cold Spray Kinetic Energy Ambient or Powder gies and / or processes may be used . By use of the alloy bond

Controlled 40 layer 14 , grit blasting the substrate can therefore be avoided . Atmosphere FIGS . 1 - 3 show cross - sections of an exemplary resistor Combustion Wire Thermal Energy Ambient Wire Spray ( Flame From 10 fabricated according to an embodiment the present inven Spray ) Combustion Process tion . As shown in FIGS . 2 - 3 , an aluminum oxide or alumi Combustion Thermal Energy Ambient Powder num nitride ceramic substrate 12 is provided . It should be Powder From 45 appreciated that any acceptable ceramic or other electrically Spray ( Flame Combustion Process Spray ) non - conductive material for use in a thin film resistor may Controlled High Temperature Controlled Powder be used as the substrate 12 . In addition , it is contemplated Atmosphere Plasma Atmosphere that metallic substrates that have an electrically non - con Plasma Spray ductive surface treatment may also be used .

50 As shown for example in FIGS . 2 - 3 , the alloy bond layer A thin film resistor according to an embodiment of the 14 is deposited , such as by a PVD process , on the substrate

present invention is shown in FIGS . 1 - 6 . The thin film 12 . The alloy bond layer 14 preferably has a chemical resistor , as shown in the orientation of FIGS . 1 - 6 , has a top composition similar to or complementary to the thermally or upper side 202 ( or first side ) , opposite side ends 204 ( left ) , sprayed resistive layer 18 that is to be applied . For example , 206 ( right ) ( also referred to as " side faces ” ) , and a bottom or 55 if a copper , nickel , titanium or tantalum alloy is to be used lower side 208 ( or second side ) . The right portion 210 of the to form the thermally sprayed resistive layer 18 , a corre resistor 10 shown to the right of center line 214 is essentially sponding copper , nickel , titanium or tantalum alloy would be a mirror image of the left portion 212 of the resistor shown used for the alloy bond layer 14 . In this manner , in a to the left of center line 214 , as shown in the Figures . Thus , preferred embodiment of the invention , the alloy bond layer descriptions of the right portion 210 will also apply to the 60 14 and the thermally sprayed material essentially correspond left portion 212 , unless otherwise indicated . and have the same or a similar chemical composition . Thus ,

A thin film resistor according to an embodiment of the if a nickel chromium alloy is used to form the alloy bond present invention generally comprises a ceramic or non - layer 14 , the thermally sprayed material 16 may preferably metallic substrate 12 , an alloy bond layer 14 deposited on be a nickel chromium alloy having the same or a similar the substrate 12 , and a thermally sprayed resistive layer 18 65 chemical composition . In this manner , a chemical bond may thermally sprayed to the alloy bond layer 14 . The material to be formed between the thermally sprayed material 16 and be used in forming the thermally sprayed resistive layer 18 the material of the alloy bond layer 14 .

US 9 , 818 , 512 B2

10

The alloy bond layer 14 is preferably formed using a PVD in FIGS . 1 , 2 and 4 , may be formed to create a connection process , though other vapor deposition processes including , to the thermally sprayed resistive element 20 and thereby but not limited to , PECVD or CVD may be used . The alloy permit testing the properties of the thermally sprayed resis bond layer 14 forms a strong mechanical bond with the tive element 20 . To accomplish this , as shown in greater ceramic or nonmetallic surface of the substrate 12 . 5 detail in FIGS . 2 and 4 , a vapor deposited adhesion layer 28 As shown in FIGS . 2 - 3 , a thermally sprayed material 16 of an alloy , for example , an adhesion layer 28 of a titanium

is thermally sprayed onto the alloy bond layer 14 to form a alloy applied by , for example , a PVD process , is applied to thermally sprayed resistive layer 18 . The thermally sprayed a previously applied thermally sprayed resistive layer 18 . A resistive layer 18 forms a thermally sprayed resistive ele - first conductor layer 32 , for example a first conductor layer ment 20 , the size and shape of which can be adjusted during 10 32 comprising gold , is preferably vapor deposited such as by the manufacturing process . During the application of the PVD on the previously applied adhesion layer 28 . A pho thermally sprayed resistive layer 18 by a thermal spraying toresist may then be applied to the previously applied layers process , such as any described above or others known in the and patterned to further define an additional layer , if desired , art , a chemical bond is formed between the thermally of the conductor pads 38 . Once the areas where optional sprayed material 16 and the alloy bond layer 14 due to the 15 additional layers of the conductor pads 38 will be formed are similarities in their chemical composition . The thermally defined , plating may be used to form a second conductor sprayed resistive element can be sprayed , for example , to a layer 36 , comprising , for example , gold , and the photoresist thickness of at least 3 . 94 mils ( 100 micrometers ) . While the is removed . Alternately , the second conductor layer 36 may use of an alloy bond layer 14 may be preferred , it is be formed by thermal spraying . With the photoresist appreciated that a resistor may be formed on a substrate 12 20 removed , the conductor pads 38 , which may be one or according the principles of the present invention by using a multiple layers , and the adhesion layer 28 may be etched , thermal spraying process alone , without use of the alloy forming separate block resistors comprising the previously bond layer 14 , as an alternate embodiment . For example , as described thermally sprayed resistive layer 18 comprising , shown in FIG . 13 , an alternate embodiment of a resistor may for example , nickel chromium alloy , with conductor pads 38 , be formed according to the present invention with a ther - 25 which may comprise gold , at the end of each block . mally sprayed material 16 thermally sprayed directly to a As shown in FIGS . 1 - 6 , a portion of a cross - section of a substrate 12 of the resistor , without the use of an alloy bond thin film resistor 10 is shown , with a thermally sprayed layer 14 . resistive layer 18 formed from thermally sprayed material 16

In order to define the area where the alloy bond layer 14 comprising , for example , copper , nickel , titanium or tanta and / or thermally sprayed material 16 are to be applied , 30 lum , or alloys thereof . The thermally sprayed resistive layer mechanical masking may be used . This mechanical mask - 18 forms a thermally sprayed resistive element 20 of a ing , shown in FIGS . 7A and 7B , defines the net resistor area finished resistor . The thermally sprayed resistive element 20 A which in turn defines the resistance value of the subject is thus made up of feedstock particles , " drops , " " splats ” or resistors . A mechanical mask 22 is placed over the substrate . “ lamellae ” of the thermally sprayed material 16 , formed by By tailoring the size of the mechanical mask openings 24 , 35 the liquefied droplets or plastically deformed particles of the the resistor area A and the ultimate resistance value can be thermally sprayed material 16 selected . The thermally defined . The size of the mechanical mask opening 24 can be sprayed resistive element 20 will demonstrate the properties selected to achieve a resistor area A having a particular of a thermally sprayed coating using the thermal spraying resistance value . Accordingly , a method for selecting a techniques described herein , or related thermal spraying specific resistance value is provided as part of the thermal 40 techniques . Thus , the thermally sprayed resistive element 20 spraying process described herein . This method is shown will comprise particles demonstrating mechanical interlock schematically in FIG . 12 , with the steps leading up to the ing or bonding , diffusion bonding , metallurgical bonding , or thermally sprayed process to follow . The process can then other adhesive , chemical or physical bonding properties , or proceed to the additional steps shown in FIGS . 9 - 11 , combinations of these , depending on the nature and com described in greater detail below . A thin film resistor accord - 45 position of the particles of the thermally sprayed material 16 . ing to the present invention may have a low resistance value Whereas known methods of depositing a resistive element of such as a resistance value of about 10 . 0 ohms or less , or a a thin film resistor can deposit a resistive element at rates for resistance value of about 1 . 0 ohms or less . a PVD process varying between about 0 . 005 to 0 . 2 microm

Further geometry modifications can be made to the ther - eters per minute for typical materials used in thin film mally sprayed resistive element 20 , during deposition , using 50 resistor manufacturing , using a thermal spraying process , a varying hard mask geometries and after deposition using thermally sprayed resistive element can be deposited at a chemical etching , laser machining and / or grinding or abra rate of between about 10 to 60 micrometers per minute , to sive machining . Modification of these geometries affects the form a thin film resistor as described herein . resistor area A and hence the electrical properties of the While formation of the conductor pads 38 may be accom finished device . The geometry of the thermally sprayed 55 plished using a vapor deposited adhesion layer and seed resistive element 20 can be selected to achieve a particular layers ( e . g . , the PVD deposited layers that are used to initiate selected geometry having particular selected electrical prop - the electrolytic plating process , such a PVD deposited gold erties . Examples of geometries that may be used for the layer thick enough to initiate the electrolytic gold plating thermally sprayed resistive element 20 include a block process ) , followed by , for example , a plating process , other pattern , a serpentine pattern , a top hat pattern , and a ladder 60 processes and materials may be used to form the conductor pattern . Accordingly , a method for selecting a resistive pads 38 . For example , an additional mechanical mask and an material geometry to achieve specific electrical properties is additional thermal spraying process may be used to form the provided as part of the thermal spraying process and method conductor pads 38 . of forming a thin film resistor as described herein . Alternately , as shown in FIG . 15 , a typical thick film Once the alloy bond layer 14 and thermally sprayed 65 technology process as known in the art may be used to apply

resistive layer 18 are applied to the substrate 12 , conductor thick film conductor pads 34 to the surface of the substrate pads 38 , which may be single or multiple layers , as shown 12 prior to depositing the resistive materials . Thick film

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materials and processes are used to make thick film chip the alloy bond layer 14 . The parts of the thermally sprayed resistors , resistor networks , hybrid substrates , and other resistive element 20 that remains exposed after the adhesion electronic components and circuits . In the case of a ther - layer 28 and conductor pads 38 are applied may be covered mally sprayed resistor , a thick film conductor material could by the moisture passivation layer 40 , which can extend along be screen printed onto a bare ceramic substrate as a thick 5 a length of an upper surface of the thermally sprayed film conductor layer 34 , and subjected to a firing process to resistive element 20 to adjacent the adhesion layers 28 and melt the inorganic binders in the thick film paste , thereby conductor pads 38 , and may at least partially cover an upper bonding the thick film conductor layer 34 to the substrate 12 . surface the conductor pads 38 . The mechanical protection Thick film conductors may contain silver or silver alloys , layer 42 covers an upper surface of the moisture passivation copper , or gold as the conductive phase , and an inorganic 10 layer 40 , and may completely cover the moisture passivation binder such as glass to bond the conductive phase to the layer 40 . The mechanical protection layer 42 may also substrate . With the thick film conductor pads 34 applied , extend to cover edges of the upper surface of the conductor such thick film conductor pads 34 being one or multiple pads 38 . The adhesion layer 54 , third conductor layer 56 , layers , an alloy bond layer 14 may be applied , using a range fourth conductor layer 52 , barrier layer 48 and solder layer of known methods , overlapping onto the thick film conduc - 15 46 may have a first end adjacent to and abutting the moisture tor pad 34 . With the alloy bond layer 14 in place , the passivation layer 40 and mechanical protection layer 42 , thermally sprayed resistive layer 18 would be applied using extending around the side ends 204 , 206 , and extending a mechanical mask such as described . along at least a portion of the bottom 208 of the resistor , as

Termination patterns or designs can be varied to modify shown for example in FIGS . 1 and 2 . the resistor geometry in order to increase or decrease the 20 In another embodiment , shown in FIG . 14 , rather than square count of the resistor and to impact or otherwise extending beneath the conductor pads 38 as in FIG . 14 , the control the electrical properties of the finished resistor . The alloy bond layer 14 can alternately extend a shorter distance geometry of the thermally sprayed resistive element 20 may ( shown extending to line D1 in FIG . 14 ) along the upper be modified using laser trimming and / or machining pro - surface of the substrate and extending directly beneath the cesses to achieve the desired resistance value . While laser 25 thermally sprayed resistive layer 18 , but not extending trimming may be used , other processes may be used includ - beneath the adhesion layer 28 . In the embodiment of FIG . ing , but not limited to , chemical etching , grinding or abra - 14 , the adhesion layer 28 is applied directly to the substrate sive machining , to establish the final resistance value . After 12 on opposite sides of the alloy bond layer 14 and thermally the final resistance value is obtained , an overcoat 50 may be sprayed resistive layer 18 , and the additional layers may be applied to the thermally sprayed resistive layer 18 compris - 30 applied and positioned as described in connection with ing a moisture passivation layer 40 and a mechanical pro FIGS . 1 - 6 , and as shown in FIG . 14 . tection layer 42 . The moisture passivation layer 40 may be , An exemplary method of manufacturing a thin film resis for example , a polymer , while the mechanical protection tor according to the teachings of the present invention is layer 42 may be , for example , an epoxy . Those of skill in the shown diagrammatically in FIGS . 9 - 11 . As shown in FIG . 9 , art will recognize various polymers and similar composi - 35 in step 100 , a substrate 12 is selected . The substrate 12 may tions that may be used in forming an overcoat . be , for example , an aluminum oxide or aluminum nitride As shown for example in FIGS . 1 , 2 and 5 - 6 , with the substrate . In step , 103 , a mechanical mask is positioned to

overcoat 50 applied , an electrical connection from the upper define the resistor area A and therefore the resistive value V side 202 of the device to the bottom side 208 of the devices of the resistor . The size of the resistor area A and selection is made by one or more additional layers . As shown for 40 of the size of the mechanical mask openings 24 to provide example in FIGS . 2 and 5 - 6 , this may be accomplished using a particular resistor value V can be provided according to a PVD process to apply a nickel alloy adhesion layer 54 steps 101 - 103 of FIG . 12 . Using mechanical masking tech followed by a nickel alloy conductor layer 56 ( which may n iques , in step 104 , the alloy bond layer 14 is deposited . The also be considered and / or referred to as a third conductor alloy bond layer 14 may be a thin film nickel alloy applied layer ) overlapping the conductor pads 38 and extending 45 by a PVD process . In step 105 , a thermal spraying process around the end of the device onto the bottom of the substrate is used to spray the thermally sprayed material 16 on the 12 . Once the PVD adhesion layer 54 and third conductor alloy bond layer 14 , to form a thermally sprayed resistive layer 56 are deposited , a fourth conductor layer 52 , for layer 18 . The thermally sprayed material 16 may be a copper example , copper , may be plated to the desired thickness alloy , nickel alloy , titanium alloy or tantalum alloy . In an followed by a nickel barrier layer 48 . The final plating step 50 exemplary process of manufacturing a thin film resistor may be the application of a tin / lead or lead free solder 46 according to the present invention , a nickel alloy bond layer finish . While PVD deposited nickel alloys were used for the 14 is used , and is then thermally sprayed with a nickel alloy adhesion layer 54 , followed by a plated copper conductor thermally sprayed material 16 . layer 52 , alternative processes and materials may be used to To form conductor pads 38 , as shown in step 106 , an alloy form the connection from the upper side 202 to the bottom 55 adhesion layer 28 is deposited on a top or first surface of the side 208 of the device . thermally sprayed resistive layer 18 adjacent the opposite As shown in FIGS . 1 - 6 , in an embodiment of a resistor of side ends of the thermally sprayed resistive layer 18 . The

the present invention , the alloy bond layer 14 extends along alloy adhesion layer 28 is also applied to at least a portion a majority of the upper surface of the substrate 12 . The of a top or first surface of the alloy bond layer 14 on opposite thermally sprayed resistive element 20 extends along a 60 sides of the thermally sprayed resistive layer 18 , as shown majority of the alloy bond layer 14 . The adhesion layer 28 in FIGS . 1 and 2 . The alloy adhesion layer 28 may be a PVD and conductor pads 38 are positioned on opposite side ends applied thin film titanium alloy . of the thermally sprayed resistive element 20 , and at least As shown in FIG . 9 , the steps for formation of conductor partially overlap an upper surface of the thermally sprayed pads 38 are shown diagrammatically . In step 107 , a first resistive element 20 at the opposite side ends . The adhesion 65 conductor layer 32 is applied over the alloy adhesion layer layer 28 and conductor pads 38 may extend toward the side 28 . The first conductor layer 32 may be a PVD applied thin ends 204 , 206 of the resistor 10 and to adjacent the end of film gold or copper conductor layer . In step 108 , a second

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conductor layer 36 is applied over the first conductor layer of an alloy bond layer 14 . The resistor may be further 32 . The second conductor layer 36 may be gold or copper , fabricated using additional layers and processes as described and may be applied by thermal spraying or plating tech - herein . niques . The conductor pads 38 may be formed by applying a

Turning to FIG . 10 , the overcoat 50 is applied along a 5 thermally sprayed alloy directly to the thermally sprayed length of the upper surface of the thermally sprayed resistive resistive layer 18 to form the conductor pads 38 , without layer 18 and covering the majority of the thermally sprayed applying an adhesion layer 28 . resistive layer 18 , and portions of the conductor pads 38 , as As shown in FIG . 20 , a thermally sprayed alloy may be shown in FIGS . 1 and 4 . In step 109 , the moisture passiva applied directly to the surface of the substrate 12 to form a tion 40 is applied . The moisture passivation layer 40 may be 10 thermally sprayed conductor layer 58 , prior to applying the

alloy bond layer 14 , with the thermally sprayed conductor applied by screen printing . The moisture passivation layer layer 58 acting as the conductor pads . The alloy bond layer 40 covers a length , which may be a majority of the length , 14 may then be applied directly to the surface of the of the upper surface of the thermally sprayed resistive layer substrate 12 , overlapping onto the thermally sprayed con 18 , and may extend adjacent to and may overlap edge 15 ductor layer 58 . The thermally sprayed alloy is then applied portions of the conductor pads 38 , as shown in FIG . 4 . In to the surface of the alloy bond layer 14 including an area of step 110 , the mechanical protection layer 42 is applied , such overlap on the thermally sprayed conductor layer 58 . Vari as by screen printing . The mechanical protection layer 42 ous additional layers as described herein may be also covers a central portion of the moisture passivation layer 40 , applied . and may also cover portions of the top surface of the 20 A PVD applied copper alloy conductor layer may be conductor pads 38 adjacent to the moisture passivation layer applied directly to the surface of the conductor pad 38 , 40 , as shown in FIGS . 1 , 2 and 4 . The overcoat 50 assists in extending onto the surface of the substrate 12 , around the sealing and protecting portions of the upper surface of the side ends 204 , 206 of the resistor and onto the bottom of the resistor . substrate 12 , thereby replacing the nickel alloy adhesion

Turning to FIG . 11 , an electrical connection is provided 25 layer 28 and the nickel alloy conductor layer 32 . from the top side 202 of the resistor ( in the orientation A PVD copper alloy may also be applied in combination shown in the Figures ) to the bottom side 208 of the resistor . with an alloy adhesion layer , such as a nickel alloy , directly In step 111 , a nickel alloy adhesion layer 54 is applied to the to the surface of the conductor pads 38 , extending onto the substrate , extending along a top surface of the substrate 12 surface of the substrate 12 , around the side ends 204 , 206 of adjacent the side ends of the alloy bond layer 14 , along 30 the resistor and onto the bottom of the substrate 12 , thereby opposite side surfaces of the substrate , and along portions of replacing or as an alternative to the nickel alloy adhesion the bottom surface of the substrate 12 , as shown in FIGS . 1 , layer 54 and the nickel alloy conductor layer 56 shown in 2 , 5 and 6 . The alloy adhesion layer 54 may be a nickel alloy , FIG . 5 . and applied by a PVD process . In step 112 , a third conductor FIG . 8A shows a top view of a resistor 10 made according layer 56 is applied over the alloy adhesion layer 54 and 35 to an embodiment of the present invention using thermal extending from adjacent opposite ends of the mechanical spraying techniques , and FIG . 8B shows a bottom view of protection layer and overlapping opposite top surfaces of the the resistor 10 . A finished thin film resistor according to the conductor pads 38 , along opposite side surfaces of the invention has an appearance similar to typical thin film chip substrate , and along portions of the bottom surface of the resistors made without the benefit of the thermal spraying substrate 12 , as shown in FIGS . 1 , 2 , 5 and 6 . The third 40 techniques described herein , but can be produced at a much conductor layer 56 may be a PVD applied thin film nickel lower cost and at resistance values well below those of alloy conductor layer . In step 113 , a fourth conductor layer typical thin film product . 52 is applied overlapping the third conductor layer 56 , as sample thin film resistor was created using a thermal shown in FIGS . 1 , 2 , 5 and 6 . The fourth conductor layer 52 spray technique according to the present invention , shown in may be plated nickel or copper . In step 114 , a nickel barrier 45 FIGS . 16 - 19 . FIGS . 16 - 19 show enlarged images of cross layer is applied , such as by plating . In step 115 , a finishing sections of an exemplary thin film resistor according to the solder layer 46 is applied , which may be “ hot dipped ” or teachings of the present invention at various magnifications . plated tin or tin / lead alloy . As shown in FIGS . 16 - 19 , a thin film resistor 10 was formed

It is appreciated that the steps shown in FIGS . 9 - 12 can with an aluminum oxide substrate 12 . A PVD applied thin take place in an order accommodating the fabrication and 50 film nickel alloy bond layer 14 was applied to a portion of manufacturing needs and equipment of a thin film resistor the top surface of the substrate 12 . A nickel chromium alloy manufacturer . FIGS . 9 - 12 show steps of manufacturing a was thermally sprayed over a portion of the alloy bond layer thin film resistor according to the present invention in an 14 to form a thermally sprayed resistive element 20 . A illustrative order , however , there may be variations in the moisture passivation layer 40 was screen printed on a order . In addition , those of skill in the art of thin film 55 portion of the upper surface of the thermally sprayed resis resistors will appreciate that several manufacturing variables tive layer 18 , and a mechanical protection layer 42 was ( e . g . , type of equipment used , pressure , temperature , envi - screen printed over a portion of the moisture passivation ronment ) may be used and / or otherwise adjusted during layer 40 to form an overcoat 50 . various steps in the manufacturing process . To form the conductor pads 38 , a PVD applied thin film

It is further appreciated that , while various adhesion , bond 60 titanium alloy adhesion layer 28 was applied at sides of the and conductor layers have been described , not all are nec - upper surface of the thermally sprayed resistive layer 18 . A essary in order to create a resistor according to the present PVD applied thin film gold first conductor layer 32 was invention . Examples of variations in the layers include , but applied over the alloy adhesion layer 28 . A gold second are not limited to , the following . conductor layer 36 was plated over the first conductor layer

As shown in FIG . 13 , a thermally sprayed resistive layer 65 32 . 18 may be applied directly to the surface of a substrate 12 , To electrically connect the upper side and the lower side to form thermally sprayed resistive element , without the use of the resistor , a nickel barrier layer 48 was applied by

14

nt .

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plating running from the conductor pads 38 along the sides 4 . The thin film resistor of claim 1 , wherein the alloy bond of the substrate 12 , and along a portion of the bottom of the layer comprises an alloy of copper , nickel , tantalum or substrate . A thin film nickel alloy conductor layer 56 was titanium . applied by PVD over the adhesion layer . A copper conductor 5 . The thin film resistor of claim 4 , wherein the thermally layer 52 was applied by plating over the nickel alloy 5 sprayed resistive element is chemically bonded to the alloy conductor layer 56 . A nickel barrier layer 48 was applied by bond layer . plating over the copper conductor layer 52 . A hot dipped 6 . The thin film resistor of claim 1 , wherein the thermally lead free solder layer 46 was applied over the nickel barrier s prayed resistive element is formed from particles of a layer 48 . thermally sprayed material demonstrating mechanical bond

In the examples shown in FIGS . 16 - 19 , a nickel chro - 10 ing , mechanical interlocking , diffusion bonding , or metal mium alloy was used as the thermally sprayed material 16 . lurgical bonding . In addition , low resistance value thin film resistors can also 7 . The thin film resistor of claim 1 , wherein the thin film be made according to the present invention using other metal resistor has a resistance value of 10 . 0 Ohms or less . alloys such as MANGANIN® and EVANOHM® , or metal 8 . The thin film resistor of claim 1 , wherein the thin film alloys including but not limited to those comprising copper , 15 resistor has a resistance value of 1 . 0 Ohms or less . tantalum and titanium . The thermally sprayed material 16 9 . A method of making a thin film resistor , the method may be a combination of alloys selected to achieve particu - comprising depositing an alloy bond layer on a substrate and lar electrical properties , such as a particular temperature thermally spraying a thermally sprayed material using a coefficient or resistance ( TCR ) profile ( e . g . , a net flat TCR thermal spraying process directly on at least a portion of the profile ) or resistivity . 20 alloy bond layer to form a thermally sprayed resistive

It will be appreciated that the foregoing is presented by way of illustration only and not by way of any limitation . It 1 0 . The method of claim 2 , wherein the step of forming is contemplated that various alternatives and modifications conductor pads comprises the steps of : may be made to the described embodiments without depart depositing adhesion layers adjacent sides of the thermally ing from the spirit and scope of the invention . Having thus 25 sprayed resistive layer and over portions of the alloy described the present invention in detail , it is to be appre bond layer ; ciated and will be apparent to those skilled in the art that depositing first conductor layers over the adhesion layers ; many physical changes , only a few of which are exemplified and in the detailed description of the invention , could be made plating second conductor layers over the first conductor without altering the inventive concepts and principles 30 layers . embodied therein . It is also to be appreciated that numerous 11 . The method of claim 9 , wherein the thermally sprayed embodiments incorporating only part of the preferred material is applied at a deposition rate of at least 10 embodiment are possible which do not alter , with respect to micrometers per minute . those parts , the inventive concepts and principles embodied 12 . The method of claim 9 , wherein the thermally sprayed therein . The present embodiment and optional configura - 35 resistive element has a thickness of at least 1 . 0 micrometers . tions are therefore to be considered in all respects as 13 . The method of claim 9 , wherein the thermally sprayed exemplary and / or illustrative and not restrictive , the scope of resistive element comprises an alloy of copper , nickel , the invention being indicated by the appended claims rather tantalum or titanium . than by the foregoing description , and all alternate embodi 14 . The method of claim 13 , wherein the alloy bond layer ments and changes to this embodiment which come within 40 comprises an alloy of copper , nickel , tantalum or titanium . the meaning and range of equivalency of said claims are 15 . The method of claim 14 , wherein the thermally therefore to be embraced therein . sprayed resistive element is chemically bonded to the alloy

bond layer . What is claimed is : 16 . The method of claim 9 , wherein the thermally sprayed 1 . A thin film resistor comprising : 45 material is thermally sprayed at a rate of at least 10 microm a substrate ; eters per minute . an alloy bond layer deposited on the substrate ; and 17 . The method of claim 9 , wherein the thin film resistor a thermally sprayed resistive element thermally sprayed has a resistance value of 10 . 0 Ohms or less .

directly on at least a portion of the alloy bond layer . 18 . The method of claim 9 , wherein the thin film resistor 2 . A method of forming a thin film resistor , comprising the 50 has a resistance value of 1 . 0 Ohms or less .

steps of : 19 . A thin film resistor , comprising : providing a substrate having a first surface , side surfaces , a substrate having a first surface and an opposite second

and a second surface opposite the first surface ; surface ; depositing an alloy bond layer directly over at least a an alloy bond layer deposited on at least a portion of the

portion of the first surface ; first surface of the substrate ; thermally spraying a thermally sprayed resistive layer a thermally sprayed resistive layer thermally sprayed

directly over at least a portion of the alloy bond layer , directly on at least a portion of the alloy bond layer ; wherein the thermally sprayed resistive layer is applied conductor pads provided adjacent sides of the thermally at a rate of at least 10 micrometers per minute ; sprayed resistive layer and in contact with at least a

forming conductor pads adjacent sides of the thermally 60 portion of the alloy bond layer ; sprayed resistive layer and in contact with at least a an electrical connection connecting the first surface to the portion of the alloy bond layer ; and second surface .

electrically connecting the first surface and the second 20 . The thin film resistor of claim 19 , wherein the surface of the resistor . conductor pads comprise first conductor layers and second

3 . The thin film resistor of claim 1 , wherein the thermally 65 conductor layers . sprayed resistive element comprises an alloy of copper , 21 . The thin film resistor of claim 20 , further comprising nickel , tantalum or titanium . adhesion layers beneath the first conductor layers .

55

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22 . The thin film resistor of claim 19 , wherein the substrate , and at least partially along portions of the electrical connection comprises alloy adhesion layers second surface of the substrate ; extending from adjacent the conductor pads , along the sides depositing third conductor layers over the adhesion lay of the substrate , and at least partially along portions of the ers ; and second surface of the substrate . 5 plating fourth conductor layers over the third conductor

23 . The thin film resistor of claim 20 , wherein the layers . electrical connection further comprises third conductor lay 28 . The method of claim 27 , further comprising applying ers applied over the adhesion layers . barrier layers over the fourth conductor layers ; and , applying 24 . The thin film resistor of claim 23 , wherein the solder over the barrier layers . electrical connection further comprises fourth conductor 10 29 . The method of claim 2 , further comprising providing layers applied over the third conductor layers .

25 . The thin film resistor of claim 24 , further comprising an overcoat over exposed parts of the thermally sprayed barrier layers applied over the fourth conductor layers . resistive layer .

26 . The thin film resistor of claim 25 , further comprising 30 . The method of claim 29 , wherein the step of providing a solder finish provided over the barrier layers . an overcoat comprises the steps of :

27 . The method of claim 10 , wherein the step of electri providing a moisture passivation layer over at least a cally connecting the first surface and the second surface portion of the thermally sprayed resistive layer ; and comprises the steps of : providing a mechanical protection layer over at least a

depositing adhesion layers adjacent the conductor pads , portion of the moisture passivation layer . along portions of the first surface and sides of the * * * *

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